Move all lua related files to lua/ subfolder

Also remove the lexers sub directory from the Lua search path.
As a result we attempt to open fewer files during startup:

 $ strace -e open -o log ./vis +q config.h && wc -l log

In order to avoid having to modifiy all lexers which `require('lexer')`
we instead place a symlink in the top level directory.

 $ ./configure --disable-lua
 $ rm -rf lua

Should result in a source tree with most lua specifc functionality
removed.

1 files changed, 89 insertions, 0 deletions

diff --git a/lua/lexers/groovy.lua b/lua/lexers/groovy.lua
new file mode 100644
index 0000000..d23a5a1
--- /dev/null
+++ b/lua/lexers/groovy.lua
@@ -0,0 +1,89 @@
+-- Copyright 2006-2016 Mitchell mitchell.att.foicica.com. See LICENSE.
+-- Groovy LPeg lexer.
+
+local l = require('lexer')
+local token, word_match = l.token, l.word_match
+local P, R, S = lpeg.P, lpeg.R, lpeg.S
+
+local M = {_NAME = 'groovy'}
+
+-- Whitespace.
+local ws = token(l.WHITESPACE, l.space^1)
+
+-- Comments.
+local line_comment = '//' * l.nonnewline_esc^0
+local block_comment = '/*' * (l.any - '*/')^0 * P('*/')^-1
+local comment = token(l.COMMENT, line_comment + block_comment)
+
+-- Strings.
+local sq_str = l.delimited_range("'")
+local dq_str = l.delimited_range('"')
+local triple_sq_str = "'''" * (l.any - "'''")^0 * P("'''")^-1
+local triple_dq_str = '"""' * (l.any - '"""')^0 * P('"""')^-1
+local regex_str = #P('/') * l.last_char_includes('=~|!<>+-*?&,:;([{') *
+                  l.delimited_range('/', true)
+local string = token(l.STRING, triple_sq_str + triple_dq_str + sq_str +
+                               dq_str) +
+               token(l.REGEX, regex_str)
+
+-- Numbers.
+local number = token(l.NUMBER, l.float + l.integer)
+
+-- Keywords.
+local keyword = token(l.KEYWORD, word_match{
+  'abstract', 'break', 'case', 'catch', 'continue', 'default', 'do', 'else',
+  'extends', 'final', 'finally', 'for', 'if', 'implements', 'instanceof',
+  'native', 'new', 'private', 'protected', 'public', 'return', 'static',
+  'switch', 'synchronized', 'throw', 'throws', 'transient', 'try', 'volatile',
+  'while', 'strictfp', 'package', 'import', 'as', 'assert', 'def', 'mixin',
+  'property', 'test', 'using', 'in',
+  'false', 'null', 'super', 'this', 'true', 'it'
+})
+
+-- Functions.
+local func = token(l.FUNCTION, word_match{
+  'abs', 'any', 'append', 'asList', 'asWritable', 'call', 'collect',
+  'compareTo', 'count', 'div', 'dump', 'each', 'eachByte', 'eachFile',
+  'eachLine', 'every', 'find', 'findAll', 'flatten', 'getAt', 'getErr', 'getIn',
+  'getOut', 'getText', 'grep', 'immutable', 'inject', 'inspect', 'intersect',
+  'invokeMethods', 'isCase', 'join', 'leftShift', 'minus', 'multiply',
+  'newInputStream', 'newOutputStream', 'newPrintWriter', 'newReader',
+  'newWriter', 'next', 'plus', 'pop', 'power', 'previous', 'print', 'println',
+  'push', 'putAt', 'read', 'readBytes', 'readLines', 'reverse', 'reverseEach',
+  'round', 'size', 'sort', 'splitEachLine', 'step', 'subMap', 'times',
+  'toInteger', 'toList', 'tokenize', 'upto', 'waitForOrKill', 'withPrintWriter',
+  'withReader', 'withStream', 'withWriter', 'withWriterAppend', 'write',
+  'writeLine'
+})
+
+-- Types.
+local type = token(l.TYPE, word_match{
+  'boolean', 'byte', 'char', 'class', 'double', 'float', 'int', 'interface',
+  'long', 'short', 'void'
+})
+
+-- Identifiers.
+local identifier = token(l.IDENTIFIER, l.word)
+
+-- Operators.
+local operator = token(l.OPERATOR, S('=~|!<>+-/*?&.,:;()[]{}'))
+
+M._rules = {
+  {'whitespace', ws},
+  {'keyword', keyword},
+  {'function', func},
+  {'type', type},
+  {'identifier', identifier},
+  {'comment', comment},
+  {'string', string},
+  {'number', number},
+  {'operator', operator},
+}
+
+M._foldsymbols = {
+  _patterns = {'[{}]', '/%*', '%*/', '//'},
+  [l.OPERATOR] = {['{'] = 1, ['}'] = -1},
+  [l.COMMENT] = {['/*'] = 1, ['*/'] = -1, ['//'] = l.fold_line_comments('//')}
+}
+
+return M